4. Patients with one or more of the following admission diagnoses (International Classification of Diseases, 9th Revision Number): pneumonia (480-486), upper respiratory infection (465), bronchitis (466), influenza (487), chronic obstructive pulmonary disease (490 to 492;496), asthma (493), viral illness (079.9)[13], dyspnea (786), acute respiratory failure (518.81), pneumonitis due to solids/liquids (507), or fever (780.6) without localizing symptoms.